Magnetotransport properties in twisted bilayer graphene at magic angle

ORAL

Abstract

Recent experimental works on magic-angle twisted bilayer graphene have pointed to the existence of insulating and superconducting phases when the flat bands are half-filled. Among the mysteries in the experiments is the observed Landau fan diagram which shows a reduction in degeneracy close to the charge neutrality point compared to that at larger twist angle. These features are a remarkable departure from theoretical expectations. In this work, we use our recently developed theory for the non-interacting band structures [1, 2] to understand the behaviors of twisted bilayer graphene under the influence of magnetic field, and offer the possible scenarios that lead to the unconventional features in the magnetotransport at charge neutrality and at half-filling.

References:
[1] M. Yankowitz, J. Jung, E. Laksono, N. Leconte, B. L. Chittari, K. Watanabe, T. Taniguchi, S. Adam, D. Graf, C. R. Dean, Nature 557, 404-408 (2018)
[2] E. Laksono, J. N. Leaw, A. Reaves, M. Singh, X. Wang, S. Adam, X. Gu, Solid State Commun. 282 38-44 (2018)

*This research is funded by Singapore Ministry of Education AcRF Tier 2 (MOE2017-T2-2-140).

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Presenters

  • Evan Laksono

    • Centre for Advanced 2D Materials and Graphene Research Centre, National University of Singapore
    • Department of Physics, National University of Singapore

Authors

  • Evan Laksono

    • Centre for Advanced 2D Materials and Graphene Research Centre, National University of Singapore
    • Department of Physics, National University of Singapore

  • Alexander Reaves

    • Yale-NUS College

  • Manraaj Singh

    • Yale-NUS College

  • Xingyu Gu

    • Centre for Advanced 2D Materials and Graphene Research Centre, National University of Singapore
    • Department of Physics, National University of Singapore

  • Jia Ning Leaw

    • Centre for Advanced 2D Materials and Graphene Research Centre, National University of Singapore

  • Nimisha Raghuvanshi

    • Centre for Advanced 2D Materials and Graphene Research Centre, National University of Singapore
    • Department of Physics, National University of Singapore

  • Shaffique Adam

    • Department of Physics and Centre for Advanced 2D Materials, National University of Singapore
    • Centre for Advanced 2D Materials and Graphene Research Centre, National University of Singapore
    • Department of Physics, National University of Singapore
    • Yale-NUS College
    • National University of Singapore